Calibrating FX-888

[ABCD]

How do you check that the dialed up temperature is what the iron is putting out?  There's the calibration screw on the temp knob, but what do you use to measure the temp at the tip?

[IanB]

A tip thermometer:



But honestly, it isn't worth it for home users. Just adjust the temperature dial to suit your working conditions. The solder should flow easily and quickly on joints, but the flux should smoke as little as possible and not char or burn.